POS1295 SYSTEMIC AND AUTO-INFLAMMATORY DISEASES OF PEDIATRIC ONSET: THE EXPERIENCE OF THE FRENCH OVERSEAS DEPARTMENTS OF AMERICA
Authors: A. Felix, F. Delion, E. Coignard, E. Martin, M. Mohamed Sahnoun, C. Hospice, E. Cuadro Alvarez, N. Elenga, M. Dramé, B. Bader-Meunier, C. Deligny, Y. Hatchuel
Journal: Annals of the Rheumatic Diseases (2022)

Background Systemic diseases of pediatric onset are more frequent in Afro-Caribbean population, especially Pediatric systemic lupus (pSLE). Objectives Our work is a retrospective study of patients followed in French overseas departments of America for systemic disease or auto-inflammatory syndrome of pediatric onset. It describes their clinical and biological specificities at diagnosis, during childhood and early adulthood. Methods Our retrospective study was conducted between 01/01/2000 and 01/09/2021. Listings of adult patients with pediatric onset and pediatric patients were obtained in each center through computerized hospital archives, list of patients followed by referent pediatricians and adult specialists in internal medicine and the French National Registry for rare disease. Data were then gathered by going through their medical files. The spectrum of diseases studied included pSLE, Sjogren syndrome, antiphospholipid syndrome (APS), connectivitis, systemic scleroderma, dermatomyositis, Systemic juvenile idiopathic arthritis (sJIA), unclassified auto-inflammatory syndrome. Results 2148 patients were identified on a 21 year-period, and 135 patients were included. Most patients diagnosed with a systemic pathology (102) suffered from pSLE (53%), followed by dermatomyositis (17%). Average follow up was 8.3 years (0.3 - 25 years), median age at last follow up was 21.2 (14 - 36.7). We found an increase in the number of new diagnoses throughout the years. For pSLE, sex repartition was 4/1 girl/boy and did not vary according to age (p= 0,31). At onset, patients had 10 Sclicc criteria (4-12) and median EULAR/ACR 2019 score was 38 (12 - 54). The combination of typical skin involvement, arthritis and fever was found for 87%. At onset, a third of patients had renal involvement, 15% had Neurolupus and 41% cardiac involvement. All patients had a positive ANA and Anti-DNA antibodies, followed by anti-Ssa/Ssb antibodies (78%), Anti-Sm (78%) and anti RNP (52%). During childhood, 54% had renal involvement and 26% suffered from Neurolupus. Patients suffered in median from 3 flares and 26% suffered from more than 5 flares during childhood. Pre-pubertal patients (26%) had worst outcomes, 93% had renal and / or neurological involvement, they had more flares (median at 5 p = 0,02) and needed an average of 4 background therapies (p = 0,04). Boys seemed to have better disease control at transition to adult care but gender was not an independent predictor of severity during childhood (p = 0,21). 17 patients had dermatomyositis, 29% of them had respiratory involvement during childhood. 33 patients had auto-inflammatory syndromes mostly sJIA (67%), 50% of them had hemophagocytic syndrome during childhood and their disease was controlled by steroids for 64%, 36% needed biotherapy. The overall mortality was 3%. Conclusion This is a large cohort of patients of Afro-Caribbean origin with a higher frequency of pSLE. Although the outcomes for these patients were similar to western countries, they had loud symptoms at onset, not corelated to delay at diagnosis. Compared to ethnic studies of North America or Africa, the French health care system being universal and free, the bias related to socio-economic status was lower. This work will continue with the exploration by transcriptomic and genetic tests for early and severe forms to identify the extra-environmental causes. The environmental factors specific to these regions should be explored in additional prospective studies. Figure 1. Clinical and biological characteristics of patients with pediatric onset systemic lupus. Orange: clinical signs at onset, Green: immunological profile, Blue: evolutive profile and proportion of organ involvement during childhood. ANA: anti-nuclear antibody. Disclosure of Interests None declared